Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss, Net of Tax (Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
(Loss) gain on derivative instruments, net of income tax benefit of $(22.7) and $(5.3), respectively
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive loss, income taxes	$ (22.7)	$ (5.3)
Accumulated Gain Loss Net Cash Flow Hedge Parent Member
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive loss, income taxes	19.1	19.1
Gain On Interest Rate Swap Net Of Income Taxe Member
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive loss, income taxes	0.3	0.4
Defined benefit pension plans and Retiree health care plan | Defined benefit pension plans, net of income benefit of $(20.4) and $(22.8), respectively
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive loss, income taxes	(23.0)	(20.4)
Defined benefit pension plans and Retiree health care plan | Retiree health care plan, net of income taxes of $1.9 and $1.6, respectively
Accumulated Other Comprehensive Income Loss [Line Items]
Accumulated other comprehensive loss, income taxes	$ 2.0	$ 1.9